The present invention relates to a mechanism for dubbing data with a magnetic recording and reproducing device having a rotary head. More particularly, the invention relates to a magnetic recording and reproducing device including such a machanism having a reproducing rotary head disk and a recording rotary head disk mounted on the same rotary shaft.
FIG. 1 is a block diagram describing an operation of dubbing data with a conventional magnetic recording and reproducing device with a rotary head. In FIG. 1, reference numeral 1 designates a first recording and reproducing unit, and 2, 3, 4, 5, and 6, a rotary shaft, a rotary transformer, reproducing rotary heads, and a rotary disk of the first recording and reproducing unit 1, respectively. The video output of the first recording and reproducing unit 1 is applied to the video input terminal 10 of a second recording and reproducing unit 9, and is then applied through a conventional sound recording circuit to rotary heads 4' and 5'. In FIG. 1, reference numerals 2', 3', 4', 5', and 6' designate a rotary shaft, a rotary transformer, recording rotary heads, and a rotary disk of the second recording and reproducing unit 9, respectively.
The operation of the magnetic recording and reproducing device thus constructed will be described. The head outputs of the magnetic recording and reproducing unit 1 are applied from the A--CH (A--channel) head 4 and the B--CH (B--channel) head 5, which is fixedly mounted on the rotary disk 6 secured to the rotary shaft 2 through the rotary transformer 3, head amplifiers, a switcher, a mixer, a demodulating circuit, etc., to a video output terminal 7. The output provided at the video output terminal 7 is supplied through a signal path 8 (cable) to the video input terminal 10 of the magnetic recording and reproducing unit 9. The signal thus inputted is a video signal. The video signal is frequency modulated and amplified by a recording amplifier shown in the block diagram. The video signal thus processed is applied to the head. The input signal is applied to the rotary transformer 3 and is recorded by the A--CH head 4' and the B--CH head 5' which are provided on the rotary disk 6'. In this manner, the dubbing operation is accomplished.
In FIG. 1, a color circuit is not shown.
The conventional dubbing mechanism using a magnetic recording and reproducing device having rotary heads, constructed as described above, requires two similar magnetic recording and reproducing units. This tends to increase the amount of mechanical vibration, jitter, etc. Furthermore, since the two units employ different running systems, the tracking thereof is rather difficult. In addition, as the signal is demodulated and then modulated again, the picture quality is unavoidably low.